The Specific Rotation of the Pure α-Anomer of a Monosaccharide

The specific rotation of the pure α-anomer of a monosaccharide is +169.7 and that of the pure β-anomer is +29.4. A solution of the pure α-anomer produces a specific rotation of +61.4. Based on this data, which of the following is correct?

A) The solution contains more of the α-anomer.
B) The solution is an equimolar mixture of the two anomers.
C) A solution of the pure β-anomer would produce the same specific rotation.
D) The change in specific rotation is due to the irreversible formation of the open-chain monosaccharide.
E) All of these.